1. Field of the Invention
The present invention relates to a method for adjusting and testing, and more particularly to a method and apparatus for automatically adjusting and testing an image sensor module.
2. Description of the Prior Art
At present, an image sensor module mainly includes a circuit board, an image sensor mounted on a center position of the circuit board, a lens barrel fixed to the circuit board, and a lens mounted in the lens barrel and located above the image sensor. During the mounting process of the image sensor module, after the lens is mounted in the lens barrel, it is needed to focus the lens, namely to adjust the distance between the lens and the image sensor. Prior methods for adjusting the lens mainly have two modes. A first mode is adopting manual operation for focusing. Because the manual adjusting and testing operation is varied with the different operators and the result thereof is depending on individual judgments, this manual operation inevitably can affect the consistency of the focusing quality of the image sensor module. A second mode is employing a focusing device capable of automatically focusing. This focusing device generally can make a motor control a focusing wheel mechanism moving downward until the focusing wheel mechanism engages with the lens. Then, the focusing operation need be performed again on the basis of comparing the parameters by the computer image processing technology.
Whereas, mechanism errors produced in the mounting process of the image sensor module, can affect the position of the lens relative to a standard reference position specified on the lens barrel. The second mode cannot correct or compensate the mechanism errors before focusing, so it is not convenience for the focusing device to make the focusing wheel mechanism engage with the lens. When the mechanism errors exceed a permitted limit, it is resulted that the focusing device cannot automatically adjust lens.